Letoff motion for looms



Nov. 15, 1949 H. A. TURNER LEToFF MOTION Foa Looms 2 Sheets-Sheet 2 Filed Nov. 24, 1947 INVENTOR, HENRY F\. TURNER. Q -lqIV/w/ AM/7X f f Patented Nov. 15,'1949 UNITED STATES PATENT OFFICE LE'roFr Mo'rIoN Fon LooMs Henry A. Turner, Union, S. C. Application November 24,1947, serial No. 781,707 1 claim. (c1. 139-110) Itis an object of this invention to provide means adapted to cooperate with the let-ofi motion in a Draper loom which will greatly improve the operation thereof, such let-off motion being shown in the patent to Draper et al. 647,815, of April 17, 1900.

This invention relates to improvements in a let-off mechanism for looms and more especially to the type of let-oli for looms known as the Roper let-oir on a Draper loom.

Heretofore the means for transmitting rotation to the let-oli mechanism of the loom has been by the use of a connecting rod being connected to the pallet lever, which is a part of the Roper let-od, and the other end of the connecting rod being connected to a driving rod arm integral with the rocker shaft of the loom.

It is an object of this invention to provide means to beY adapted to be associated with the present means employed in the Roper let-oli motion to utilize the existing cam shaft on a loom as a means of moving the pallet lever of the Roper let-oi and thus eliminating the connection between the rocker shaft and the let-off mechanism.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which Figure 1 is an elevation, partly in section, of the left-hand rear portion of a loom showing the let-off motion and looking toward the left in Figure 2;

Figure 2 is an elevation with parts removed looking at the left-hand side of Figure 1;

Figure 3 is a vertical sectional View taken along the line 3 3 in Figure 1;

Figure 4 is an elevation taken along the line 4-4 in Figure 1 and omitting the ratchet wheel;

Figure 5 is an elevation taken along the line 5 5 in Figure 4.

Referring more specifically to the drawings, the numeral I0 indicates the left-hand vertical side frame member of a loom. The rear of frame member I0 or the left-hand end as viewed in Figure 2 has a bearing portion Il therein in which is mounted one end `of a shaft I2, of a warp beam I3. The shaft I2 is held in the bearing portion II by any suitable means such as an oscillatably mounted bracket I4, which is held in the position shown in Figure 2 by a bolt I6 secured to the vertical side member I0.

The warp beam I3 has a flange I1 integral therewith which has a plurality of gear teeth I8 also integral therewith. The gear teeth I8 mesh "with a pinion 20 which is secured to apinion let-off shaft 2l, one end of which is rotatably mounted in a bearing block 22. The bearing vblock 22 is secured to the vertical side member 'it by any suitable means such asbolts 23. The free end of the shaft 2i is rotatably mounted in va bearing portion 25 which is part of a bracket 26. The bracket 26 is secured to a bracket 21 by any suitable means such as bolts 28 and the bracket 21 is secured to the real-most portion of the vertical side member II) by any suitable means such as bolts 36 (Figure 2).

The Vother end of the shaft 2|, or the lefthandend as viewed in Figure 1, has rotatably mounted thereon a collar 3I which has pivotally mounted therein as at 32 a bell crank 33 for turning the shaft 2I manually, if desired'. Between the bearings 22 and 25 and adjacent the hearing 25 is a let-off pinion shaft arm 35 which is rixedly mounted on the shaft 2l and has a conventional slidably mounted dog 3B therein at the uppermost end as viewed in Figurel. 'Ihe dos 36 meshes with ratchet teeth 31 which are an integral part of an internal gear 38. The internal gear 38 is rotatably mounted on the shaft 2I and the internal gear teeth 38a as may be observed in Figure 3 mesh with a smaller pinion cross-head gear 40 which is in turn rotatably mounted on a cam to be presently described. The diierential gear 40 has projecting therefrom pins 4I and 42 which extend to the right as viewed in Figure 1 (see Figure 3) and pass through openings or slots 43 and 44 of a conventional pinion cross head 45. The pinion cross head extends forwardly and downwardly and has an elongated slot 48 in its forward end which is mounted for sliding movement on a conventional beam lever shaft 49, the purpose of which will be later described. The pinion cross head 45 has at its rearward end a yoke portion 50 which is mounted for sliding movement on a collar 5I which has integral therewith a cam portion 52 on which the pinion cross head gear 40 is rotatably mounted.

The collar 5| and the cam 52 heretofore described are integral parts of a ratchet wheel broadly 'designated by the reference character 54 and the ratchet wheel 54 also has integral therewith an annular ring or brake drum portion 55. Mounted on the brake drum portion 55 is a brake let-orf friction clamp 58, which at its left-hand end, as viewed in Figure 2, is penetrated by a rod 59 on the upper end of which is secured a let-olf friction cam 60 and which at The ratchet wheel 54, being rotatably mounted on the shaft 2 I, is engaged by a pallet or ratchet pawl which is pivotally mounted on a stub shaft 1l which penetrates a pallet lever broadly designated by reference character 13. Thepallet lever 13 has an angular cut-awayjportion 14 (Figure 4) which is threadably penetrated by a screw 15 and the screw 15 is tightened against the stub shaft 1I thereby holding the same in a predetermined position. The free end of the pallet 10 isforced upwardly by a compression spring 16 which projects from the side of the pallet lever 13. It is obvious that the compression spring 16 will force the free end of the pallet or pawl 10 upwardly thereby forcing the other end to remain in constant engagement with the ratchet Wheel 54.

It may be observed in Figure 4 that the upper end of the pallet lever 13 has an arm 18 integral therewith which has an elongated slot 19 therein which is penetrated by a bolt 82 and which has mounted thereon aroller or bumper 83. The pallet lever 13 has at its lower end a bearing portion 85 which is oscillatably mounted on the shaft 2|. The pallet lever 13 has vertically disposed anges 89 and 81 integral therewith between which is mounted a ball portion 88 of a link lever 89. The link lever 89 extends forwardly and downwardly and is pivotally mounted as at 92 in a weight portion 99 and the weight por# tion 90 extends forwardly and is xedly secured to the shaft 49, which passes through its bearing portion 9|. The ball portion 88, being circular in shape, extends to the right in Figure 1 and slidably penetrates a conventional depending controlling lever 93 which extends upwardly and is pivotally mounted on a bolt 94. The controlling lever 93 has a stud shaft 98 ,extending therefrom on which is pivotally mounte ed the lower end of a conventional whip roll vibrator rod 99 which has loosely mounted thereon a preventer compression spring I 99 and at its upper end it has a preventer spring collar II which engages a similar collar |02 and the collar |02 has a pin |03 extending therefrom on which is pivotally mounted a whip roll lever |04 which extends upwardly to a conventional whip roll, not shown. i

The stud shaft or bolt 94 penetrates a controlling lever stand 95 which is secured to the vertical side member I0 and the controlling lever stand 95 has a projection 95 thereon. The whip roll lever 99 slidably penetrates this projection 96 and the projection 95 retains the end of the spring |00. l

s By referring to Figure l, it may be observed that the lower end of the pallet lever 13 is confined from lateral movementon the shaft 2| by a collar |05 which is fixedly secured to the shaft 2|. The beam lever shaft 49 is mounted in a bearing |99 secured to the vertical side member I0 and the shaft 49 extends beyond the bearing |06 and has fixedly secured thereto a beamlever |08 which'has at itsupper end a pad or roller |09 which is in engagement with the warp |3a on the warp beam I3. The vertical side member I0 has an opening IIO therethrough, through which a conventional cam shaft extends. The cam shaft III is rotatably mounted in a bearing ||2 which is secured to the vertical side member I0, by any suitable means such as bolts I I3. The shaft I I is confined from lateral movement by a collar |I4 and the extreme left-hand end of the cam shaft I|| is viewed in Figure 1 has secured thereon a cam member IIB. The cam member H6 is secured to the shaft III by any suitable means such as a screw II1 and the cam member IIE is a part of my invention and engages the bumper or roller 83 which is secured to the pallet lever 13. The pallet lever 13 as heretofore described is another of the parts comprising this invention.

Method of operation When the warp on warp beam is in process and has attained its maximum tension, thereby increasing the pressure upon the whip roll, which is not shown, it acts through the whip roll lever vibrator rod |04 and moves the lower end of the controlling lever 93 to the right in Figure 2 and increases `the length of the stroke of the pallet lever 13 toward the front of the loom. This stroke of the controlling lever 93 is also affected by the tension on the vibrator rod spring |00. As this spring is compressed any. pressure on the whip roll, not shown, resulting fromnwarp tension, tends to overcome the force of this spring, to move the lower end of the controlling lever 93 toward the front of the loom. Thus, the stroke of the controlling lever in this direction ls determined.

VSince the ball 88 of the controlling lever 89 operates half in the controlling lever 93 and half in the pallet lever 13, the pallet lever` 13 is also moved toward the front ofthe loom when the controlling lever moves in this direction.- This controls the stroke of the pallet lever and its action, inrturn, governs the number of teeth on the let-off ratchet wheel that the pallet10 1ndexes. The beam lever |08 being secured to the beam lever shaft 49 also controls the length of stroke of the pallet lever 13. The more yarn that there is lon the warp beam I3, the higher the ball portion 88 of the controlling lever 89 will be in the slots ofthe controlling lever and the pallet lever, since clockwise rotation of the shaft 49 in Figure 2 will raise weighted arm 90.

' As the warp |3a is consumed from the warp beam I3, however, the diameter of the mass I3a constantly decreases and the pad or roller |09 Will move toward the axis of the warp beam I3 and the rear end of the weight portion 90 will descend so that the connecting ball 89 will move away from the fulcrum point 94 (Figure 2) of the controlling lever 93 and toward the pivot point of the pallet lever 13 which is the pinion let-orf shaft 2|. rThis results in increasing the throw of the pallet lever 'I3 lwhen the cam II6 engages roller 83, and consequently increases the stroke of the pallet 10, by setting its starting point further backY along the ratchet wheel 54, so' that a greater number of teeth :will be traversed, although thevthrow or swing of the controlling lever 93 remain-s substantially constant, varying slightly, of course, for variations in the warp tension.. It is thus seen that the pallet lever 13 is moved to the right in Figure 2 and in the approximate `position shown in Figure 2 by the means just described.

My invention consists of the cam H6 which is secured to the cam shaft Il I and the arm 18. The cam IIS, as it rotates, will engage the roller or bumper 83 of the pallet lever to thereby move the pallet lever 13 from right to left in Figure 2 and the pallet 10, being in engagement with the ratchet wheel 54, will cause the same to rotate in a counter-clockwise manner as viewed in Fgure 2.

The ratchet wheel 54 is prevented from overrunning as the let-off takes place by the conventional friction clamp 58 which is mounted on the annular projection 55 which is integral With the ratchet wheel 54.

As has been heretofore described, the cam portion 52 being an integral part of the ratchet wheel 54 will rotate only when the ratchet Wheel 54 is caused to turn. The cam 52, collar 5| and drum 55 are integral, and, as may be observed in Figure 3, it may be seen that the pinion cross head gear 40 moves or circles around the pinion let-oi shaft 2l, however, it does not have a revolving or rotative action. The pinion cross head gear 40 is prevented from rotating about the shaft 2l by the pins 4I and 42 which are engaged by the pinion cross head 45 as heretofore described.

The revolving of the pinion cross head gear 49, it being partially in engagement with the internal gear 38, will cause the same to rotate in a clockwise direction as observed in Figure 3, and since the ratchet teeth 31 of the internal gear 38` are engaged by the dog 36 of the let-01T pinion shaft arm 35, which is fixedly secured to the shaft 2l, it is obvious that the pinion 20 on the shaft 2! will be turned and the pinion 29, being in engagement with the gear teeth I8 of the flange Il of the Warp beam I3, will cause the Warp beam to turn slightly or in step by step relation in a clockwise direction, as observed in Figure 2.

It is thus seen that the cam Wheel H6 on the conventional cam shaft III will transmit incremental oscillatory motion to the pallet lever for driving the let-off mechanism and to, in turn, transmit oscillatory motion to the whip roll, not shown, thus eliminating cumbersome connections between the rocker shaft or sword and the let-off mechanism, such as the link d6 shown in the patent to Draper et al., Number 647,815 of April 17, 19.00.

In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposes of limitation, the scope of the invention being defined in the claim.

I claim:

In a loom having a warp beam and a warp let-olf motion comprising a ratchet wheel having a driving connection with the warp beam for imparting rotation thereto, said loom also having a depending controlling lever pivotally mounted at its upper end and extending alongside and in spaced relation to the ratchet wheel, said loom also having an uprising oscillatable pallet lever disposed between the depending controlling lever and the ratchet wheel and pivoted at its lower end on the same center as the ratchet wheel, the depending controlling lever and the oscillatable pallet lever both having longitudinally extending grooves in their proximate sides and having a ball portion slidably mounted in the grooves and having a warp beam feeler connected thereto whereby the amount of warp on the warp beam Will regulate the position of the ball portion relative to the depending controlling lever and the oscillatable pallet lever, a pivoted dog on the upper end of the oscillatable pallet lever and engaging the ratchet Wheel, said loom also having a cam shaft provided with an end which extends outwardly into the same vertical plane in which the ratchet wheel is disposed, a cam wheel mounted on the extending end of the crank shaft and having a plurality of high points on its periphery, an arm secured to the upper end of the oscillatable pallet lever and extending towards the cam wheel and whose free end is adapted to be engaged by the high points on the cam wheel to impart oscillation to the oscillatable pallet lever to impart a partial rotation to the ratchet wheel.

HENRY A. TURNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 95,197 Collins Sept. 28, 1869 348,335 Nightingale et al. Aug. 31, 1886 1,448,081 Northrop Mar. 13, 1923 1,586,982 Epps June 1, 1926 2,435,437 Foster et al. Feb. 3, 1948 

